var adapter = function() {
  var windowWidth = document.documentElement && document.documentElement.clientWidth || document.body.clientWidth || window.innerWidth;
  var scale = parseFloat(windowWidth / 375);
  var root = document.getElementsByTagName('html')[0];
  root.style.fontSize = 20 * scale + 'px';
  root.style.display = 'block'
}
adapter();
window.onresize = adapter
